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KOYO / Single-row / inch series

KOYO A4050/138

Tapered roller bearings technical reference with manufacturer-sourced dimensions, characteristics and engineering resources.

Technical data available
Bore diameterd
12.7 mm
Outside diameterD
34.988 mm
WidthB
10.988 mm
Dynamic load ratingC
15.7 kN
Static load ratingC0
11.9 kN
Limiting speednG
12000 r/min

Use this page as a technical reference. Verify the current manufacturer specification and the complete application requirements before selection.

Technical data

Product specifications

Metric and imperial values are paired where the manufacturer provides both. Expand a section to review its parameters.

Core specifications9 parameters
Core specifications
ParameterSymbolValue
Variant / constructionSingle-row / Inch series
Bore diameterd12.7 mm
Outside diameterD34.988 mm
WidthB10.988 mm
Basic dynamic load ratingC15.7 kN
Basic static load ratingC011.9 kN
Fatigue load limitPu1.55 kN
Limiting speednG12000 r/min
Mass≈m0.055 kg
Manufacturer Identity2 parameters
Manufacturer Identity
ParameterSymbolValue
BrandKOYO
Official Class Key050-010-020
Classification2 parameters
Classification
ParameterSymbolValue
Official Category PathTapered roller bearings - Single-row - Inch series
Official Classification 1Tapered roller bearings / Single-row / Inch series
Technical Data23 parameters
Technical Data
ParameterSymbolValue
d12.700 mm
D34.988 mm
T10.998 mm
B10.988 mm
C8.730 mm
R(Min.)1.2 mm
R1(Min.)1.2 mm
Basic Load Ratings : Cr15.7 kN
Basic Load Ratings : C0R11.9 kN
Fatigue Load Limit : Cu1.55 kN
Limiting Speeds(Grease Lub.)12000 min-1
Limiting Speeds(Oil Lub.)17000 min-1
Load Center Spread : A8.3 mm
Constant :E0.45
Axial Load Factors : Y11.33
Axial Load Factors : Y00.73
Da18.5 mm
Db17.0 mm
Da29.0 mm
Db32.0 mm
Ra(Max.)1.2 mm
Rb(Max.)1.2 mm
Mass(Refer.)0.055 kg

Technical documents & data sheet

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Record identity
KOYO A4050/138
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